Fairfax Media revealed on Thursday that the NRL was close to finalising plans for having players' brains scanned to track the impact of concussion.

Grieve described it as a "very sensible evolution" by the NRL.

"I have had a bit of contact with the NRL and they are very focused on measures that make a lot of sense," Grieve said. "They are very advanced and are probably the leading code in Australia."

A recent study found that players from the two rugby codes are susceptible to enlarged hearts. Associate professor and cardiac scientist Sharon Kay led the study after former rugby league star Phil Blake was lucky to escape death following a heart attack.

Kay said players from rugby codes were "23 to 40 per cent" more prone to heart problems, having tested the heart of elite rugby and rugby league players with semi-professional players in each code.

"There are two reasons," Kay said. "Frontal force trauma can hit the aorta. The other is when you get tackled and then you do an explosive run, your heart has a stroke volume. Then it pumps it out in one beat, much higher than it normally would and there is pressure going through the aorta.

"Phil Blake has a big aorta and he can still do whatever he wants. It is something we monitor."

Kay and Grieve are working on a "Hearts and Minds" study involving a host of ex-Wallaby players and will involve players undertaking a 4D flow MRI. Grieve expected the study to run until March.

"A lot of these guys had big international careers and have got aortas which are starting to get out of the normal range," Grieve said. "They are at risk of aneurysm or dissections. We think that's to do with the contact and impact [from their sporting career]."